On Fri, 2007-13-04 at 17:30 +0200, Andrei Maslennikov wrote: > Performance of a single OSS depends on the perfomance of the local > ext3 backend > file system, and we were unable to push it over 750 MB/sec.
Nomenclature in such a discussion is very important. An OSS is an Object Storage Server. An OSS can contain many OSTs. An OST is an Object Storage Target. An OST is a Lustre building block constructed from a single block device, be it a single physical disk (/dev/sda for example) or a partition on a disk (/dev/sda1 for example) or an LVM LV (/dev/vg00/ost1 for example), or a software raid device (/dev/md0 for example) or the block device a hardware RAID card presents to the operating system. > The advice of Andreas > from Clusterfs is to use 3 OSTs inside one OSS and stripe files over > all three of them. Right. I believe the 3 OSTs he recommended you use would be the three RAID disks you have in the machine. > Time ago we have however considered and discarded this solution as we > wanted > to ensure that every file is confined to one and only one OSS capable > to deliver > 0.9-1 GB/sec. Do you really mean OSS here or OST? Given the 3 OSTs you would put on the 3 RAID cards you have in your OSS, this would meet your requirements wouldn't it? > Setting the filesystem default stripe count to 3 may lead to a > situation > when a file may end up on different OSS machines, I believe Andreas described striping across the 3 OSTs in that single OSS machine. > and that's exactly what we want > to avoid. (I have asked Andreas to comment on the configuration; would > it be possible > to migrate to striping over 3 OST per OSS, and still ensure the OSS > confinement, Sure. I do think that is what Andreas was suggesting. b. _______________________________________________ Lustre-discuss mailing list [EMAIL PROTECTED] https://mail.clusterfs.com/mailman/listinfo/lustre-discuss
